Paul Howes resigns as AWU national secretary

Prominent union boss Paul Howes has quit his role as national secretary of the Australian Workers Union (AWU), and says he is not leaving to try and join Parliament immediately.

Mr Howes released a statement online following hours of speculation he would be stepping down for a corporate job.

He says he is not ruling "anything in or anything out" when it comes to a possible political career.

"What I do in the future, I don't know," he told Sky News.

He says entering Parliament was never his primary motivation in life, describing speculation he could one day lead the Labor Party as "very flattering".

"In terms of Parliament I'm not ruling anything in or anything out but I am not stepping down from this role to pursue a career in parliamentary politics, I want to do other things," he said.

He says he has been contemplating his next steps for some time and plans to leave the public spotlight for a "very long period of time".

"The time is right for me to make a change. Over the next little while I'll make my decision about what I will do," he said.

Mr Howes says he wants to go back to studying, having left school at 14.

A friend of Mr Howes, who did not want to be named, told the ABC it had long been the union leader's intention to go into the corporate sector before seeking any political career because it would enable him to eventually present himself as a consensus candidate to the public, with experience on both sides.

Some in Labor believe Mr Howes, who turns 33 this year, could one day lead the party.

He leaves the AWU united, with a robust membership and strong finances.

Opposition Leader Bill Shorten

Mr Howes shot to prominence when he went on Lateline on the night Kevin Rudd was deposed as prime minister and publicly backed his removal from the Labor leadership – something he has since admitted to regretting.

Mr Howes published a book of his account of the 2010 election campaign called Confessions Of A Faceless Man – a play on the nickname the Liberals awarded to him and other factional bosses instrumental in replacing Mr Rudd.

Labor senator Don Farrell, who along with Mr Howes was among one of the last factional and union leaders to continue to stand by former prime minister Julia Gillard, says he is surprised and disappointed by today's decision.

Howes encouraged to contribute to public debate

Parliamentarians from both sides, including Mr Howes's one-time mentor Opposition Leader Bill Shorten, are calling on him to continue contributing to the public debate.

"I hope that Paul will continue his vast contribution to workers' rights in the years to come," Mr Shorten said in a statement.

"It was my privilege to work with Paul at the AWU. When I left, I knew I was leaving the delegates and members in good hands when I supported Paul to replace me.

"He leaves the AWU united, with a robust membership and strong finances."

Mr Howes also won praise from some surprising quarters, with Education Minister Christopher Pyne urging him to continue contributing to the public debate.

"I assume Paul Howes is making a play for Federal Parliament and he certainly has a lot more ideas about the future of Australia and what needs to be done about policy than the current crop of people who currently represent the Labor Party," Mr Pyne said.

"He should use this opportunity to fly free from the union movement and cast out in different directions."

Cameron says it is a bad time for change of AWU leadership

"I hope that he continues doing work that's actually for the good for the nation because Australia needs people like Paul Howes – someone who's young, intelligent and able to deliver some amazing things," Mr Mitchell told reporters outside Parliament.

"I think whatever he goes and does ... I'm sure he'll be extremely good at."

Mr Mitchell denied there was any conflict of interest with Mr Howes's upcoming marriage to Qantas executive Olivia Wirth, given some of his members are Qantas workers.

But Labor senator and former union boss Doug Cameron says now is the worst time for a change in the leadership of the union movement because of what he says are the Abbott Government's "attacks" on workers.

"I have to say, given the attacks that the trade union movement is under by this Government, given the attacks that workers are under by the Abbott Government, given the push to get WorkChoices by stealth in, then I think every talented union leader's focus should be on looking after working people," Senator Cameron said.

"But people make their own choices."

But Mr Howes, who will step down in July, says the union movement will continue to perform just as strongly without him.